Container support apparatus

ABSTRACT

An apparatus for supporting a flexible can, such as a plastic ham can, during the operation wherein the top of the can is seamed to the can body. The apparatus provides support structure integrally mounted in the can closing chamber. The support structure is pneumatically openable and closeable to receive and support a flexible can during seaming thereof.

United States Patent Smithers 1 Apr. 25, 1972 [541 CONTAINER SUPPORT APPARATUS 2,393,988 2/1946 Jordan et al. ..53/97 3,491,936 l/l970 Fox ..229/5.6

[72] Inventor: James P. SmIthers, Glen Ellyn, Ill.

[73] Assigncc: Armour and Company, Chicago, Ill. Emmmer-Travls McGehee Attorney-Carl C. Batz and Frank T. Barber {22] Filed: June 3,1970 III I Appl. No; 43,]5] [57] ABSTRACT An apparatus for supporting a flexible can, such as a plastic ham can, during the operation wherein the top of the can is 52] [1.5. (I ..53/86 seamed to the can body The apparatus provides Support l l 31/02 structure integrally mounted in the can closing chamber. The Field Of Search 97 support structure is pneumatically openable and closeable to receive and support a flexible can during seaming thereof. {50] References Cited 11 Claims, 9 Drawing Figures UNITED STATES PATENTS 1,605.565 11/1926 Rooney .53/89 PATENTEUAPR 2 5 m2 SHEET 2 BF 4 0 FIG. 3

INVENTOR James I? Sm/fhers ATT). a?

PATENTEBAPR 25 I972 7% 657, 8 59 SHEET u 0F 4 IN VEN TOR James P. Smifhers CONTAINER SUPPORT APPARATUS BACKGROUND OF THE INVENTION Improved methods and materials for packaging food products are constantly being sought. As a result of such research, food items which had been packaged solely in steel cans have recently been offered to consumers in a variety of improved packages. One such item is the canned ham, which is now available in a reuseable, plastic can.

Although the plastic ham can has proven to be a very desirable package for the consumer, its use creates a variety of problems for the packer. Steel ham cans are conventionally sealed under vacuum in order to expel air from the packaged product. When the cover is seamed onto the can body, care must be taken to insure a leakproof, air impermeable closure to maintain the vacuum conditions in the can to avoid spoilage.

Obtaining such a leakproof, air impermeable seal has been an acute problem with the plastic can. Since the plastic can is far less rigid than a similarly configured steel can, there is a great tendency for the can to simply distort in response to the forces exerted upon it during the seaming operation. When the distortion occurred, the seaming mechanism would be unable to fulfill its function, with the result being a can having gaps and leaks in the seam. These gaps and leaks admit air into the can, leading to spoilage of the product, and creating a very definite health hazard.

U.S. Pat. No. 3,491,936 describes the construction of a plastic harn can having a metal lid, and describes the use of a mold to hold the plastic can against distortion as it is seamed. The use of the mold has not been a completely satisfactory answer to the problem. In order to use the device, an operator must manually place the can into the mold. The mold carrying the can is placed into the vacuum seaming chamber. Upon completion of the seaming operation, the can and mold are removed from the chamber, and the seamed can is removed from the mold so that the mold can be reused. In these steps, the operator must handle both the mold and the can separately at various points in the process, which makes the process slow, time consuming, and therefore costly.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an apparatus for supporting plastic cans as they are seamed to insure a continuous, leakproofseam on the can.

A further object is to provide an apparatus useful in supporting plastic cans during closing which requires a minimum ofadditional handling steps.

A still further object is to provide an apparatus for supporting plastic cans during seaming, the apparatus being contained within the vacuum seaming chamber.

Further objects and advantages will become apparent as the specification proceeds.

A ham can closing machine is generally comprised of a large vacuum chamber, a vertically moveable base upon which the can is placed when the base is in the down position, a lid receiving structure into which the lid is placed, and a seaming chuck and rollers which seam the lid onto the can. In operation, a can having a ham therein is placed into the chamber onto the moveable base. A lid is separately placed in the lid receiving structure physically located above the moveable base and the can. The chamber door is closed and the chamber evacuated. The moveable base moves upwardly, contacting the lid and carrying the can and lid into the seaming chuck. The seaming rollers then seam the lid securely onto the can.

In the present apparatus, the moveable base is modified to include a can receiving platform, and a moveable clamp mechanism adapted to close about the can body and support the vertical walls ofthe can against distortion during the seam ing operation. The clamp mechanism is contained within the chamber and designed to operate automatically in conjunction with the vacuumizing and seaming functions.

Certain embodiments of the apparatus of the present invention will be explained in detail by reference to the accompanying drawings in which:

FIG. 1 is a front view of the apparatus in the closed position showing the vacuum chamber partially cut away,

FIG. 2 is a partial front section view of the apparatus,

FIG. 3 is a partial plan view of the apparatus showing the vacuum chamber partially cut away,

FIG. 4 is a partial side view of the apparatus,

FIG. 5 is a partial front section of the apparatus with a can in place and the clamp mechanism in the open position,

FIG. 6 is a partial front view of the apparatus with a can in place and the clamp mechanism in the closed position.

FIG. 7 is a partial front view of the apparatus with a can in place showing the moveable base at the start of its upward travel,

FIG. 8 is a partial front view partially in section with a can in place as the lid is positioned on the can body, and

FIG. 9 is a partial front view of the apparatus at the topmost travel of the moveable base showing the seaming rollers in position to seam the lid to the can body.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring to the drawings, the present apparatus is contained within a vacuum chamber 10. The clamping mechanism, indicated generally at 20, is mounted to a vertically moveable shaft 11 which can be powered in a conventional manner such as by hydraulic or pneumatic cylinders (not shown). A base plate 12 is fixed to shaft 11, having studs 13 projecting upwardly from the plate. Studs 13 aid in the proper positioning of the can on sub-base 14 as will be explained in greater detail hereinafter. Rods l5 and are fixed to sub-base 14, passing through bushings l6 and 16a in base plate 12, terminating at their lower ends in foot portions 41. Springs 17 and are wound about rods 15 and 15a and captured between collars l8 and 18a and base plate 12. Collars l9 and 1911 are fixed to rods 15 and 15a above base plate 12 and serve to limit the downward travel of the rods as the base plate travels upwardly during the seaming operation.

Referring to the clamping mechanism generally indicated at 20, curved side supports 21 are hinged at their rear portions to collar 22 which is slideably mounted on rod 40 fixed to base plate 12. Side supports 21 may be of any desired curvature or configuration, depending upon the shape of the can to be supported. in the illustrated embodiment, side supports 21 are shaped to conform to the normal configuration of a ham can, but the invention is in no way limitedto that particular shape.

Fixed to the front portions of side supports 21 are legs 23 extending downwardly beyond the lower edges of the side sup ports. The lower ends of legs 23 are connected to horizontal L-shaped arms 24 by means of pins 25 which are slideable in slots 26 provided in arms 24. Arms 24 are attached to the bottom of base plate 12 by pins 27 around which arms 24 may pivot. The opposite ends of arms 24 are fastened to piston rods 28 which are reciprocal in cylinders 29. It can be seen that in this manner the reciprocation of piston rods 28 in cylinders 29 will cause arms 24 to rotate about pivot pins 27, in turn acting upon pins 25 in slots 26 causing side supports 21 to rotate about rod 22 in alternately opened and closed positions, shown clearly in FIG. 3.

Located in the upper portions of chamber 10 is the seaming mechanism for seaming the lid to the can body. This structure is generally known and forms no part of the present invention except as modified and specifically described hereinafter. The structure generally comprises a lid receiving portion 30, a knockout pad 31 attached to piston rod 32 operable in air cylinder 33, and the seaming chuck and rollers 34. This structure is modified in the present apparatus to include first guide members 35 having bevelled portions 36, the first guide members being mounted below lid receiving portion 30, and second guide members 37 having bevelled portions 38 and mounted above lid receiving portions 30. The uppermost edges of legs 23 are also bevelled at 39 to cooperate with bevelled portions 36 and 38 in a manner to be described in detail as the specification proceeds.

OPERATION The operation of the present apparatus may be described with particular reference to FIGS. 5-9 of the drawings, depicting sequential steps in the can closing operation. While the operation is described with particular reference to a plastic ham can, it will be understood that the invention is in no way limited thereto, and may be used in the closing and seaming of a variety of cans and containers made of a variety of materials. The present apparatus is however particularly useful in the seaming of flexible containers, such as plastic contains, wherein the body of the container is susceptible to distortion during the seaming process.

In operation, a plastic can C having a shoulder portion S and a ridge portion R may be positioned on sub-base 14. A structural distinction which often exists between the conventional steel can and the plastic can should be mentioned here. Due to differences in manufacture, the steel can normally has a ridge portion as at R which is larger and more pronounced than the corresponding ridge portion R on a plastic can. For this reason, a steel can placed upon sub-base 14 will be supported by the ridge about its periphery and the flat bottom portion of the can will be above the ridge creating a space between the flat bottom of the can and the sub-base. This space may be important because often the can is filled with product to a level slightly above the top surface of the can. When such overfilling occurs, the product will be pressed down into the can by the action of the lid and knock-out pad 31. As the product is pressed into the can, the can bottom may bulge slightly, taking up the space between the can bottom and the sub-base. When this same overfilling occurs in a plastic can, however, the space between the can bottom and the sub-base is often insufficient to allow for the necessary expansion, and instead the walls of the can are distorted laterally to accommodate the product. The lateral distortion of the walls is unacceptable in that it causes an incomplete seaming of the lid to the can, resulting in a container which is not properly closed. The problem is overcome in the present apparatus through the unique construction and operation of the sub-base and its cooperation with the side supports.

The can C is placed onto sub-base l4, guided into position by studs 13 which are arranged about the periphery of subbase 14 and contact the base of the can to properly align it upon sub-base 14. A lid is separately placed in lid receiving portion 30. These operations are carried out with shaft 11 in the full down position, with foot 41 resting on the base of chamber 10. Piston rods 28 are withdrawn into cylinders 29 thereby positioning arms 24 in the outward or open position. In this position, side supports 21 are in the full open position shown in FIG. 5 and in phantom in FIG. 3.

The door 42 on the chamber is closed, closing pneumatic switch 43 which energizes the pneumatic system supplying cylinders 29. When the cylinders 29 are actuated, piston rods 28 are driven to the fully extended position, rotating arms 24 about pivot pins 27. The action of arms 24 on pins 25 moves legs 23 inwardly, rotating side supports 21 about collar 22 and rod 40. In this manner side supports 21 are brought to the closed position shown in solid lines in FIG. 3 and in FIG. 6. It should be noted with piston rods 28 in the extended position, side supports 21 fit snugly about the can C, but there remains a small space between legs 23 which can be seen clearly in FIGS. 6-8. It should further be noted that the shoulder S of the can C is slightly above the top edge of side support 21 at this point in the operation.

After the side supports 21 have been closed around the can C, shaft 11 begins its movement upward. As foot 41 rises from the base of Chamber l0, rods and 15a and sub-base 14 are allowed to drop'until collars l9 and 19a contact base plate 12, limiting the downward travel of sub-base 14. At this time, can

C is wholly supported by side supports 21 and the space between the can bottom and sub-base 14 has been enlarged by the downward movement of sub-base 14. This position is clearly illustrated in FIG. 7. By allowing sub-base 14 to fall away a short distance, sufficient space is created between the bottom of the can and the sub-base to allow for bulging of the bottom in the event that the can has been slightly overfilled.

As shaft 11 continues its upward travel, the top edge of can C contacts the lid previously placed in lid receiving portion 30. Just above the lid is knockout pad 31 which provides suffcient resistance to the continued upward travel of the can to firmly place the lid on the can, and to pack down any product which may extend above the top edge of can C. The knockout pad 31 also serves to force the can C fully down into side sup ports 21 until the shoulder S of the can C is in contact with the top edge of side supports 21. This operation takes place while a small space still exists between legs 23 whereby the can C is held loosely enough to allow it to be forced down into the side supports 21 to the shoulder S of the can. This position is clearly illustrated in FIG. 8.

Shaft 11, carrying base plate 12, sub-base l4 and a can C with a lid in place but not fixed to the can, continues upward travel. The movement of the shaft 11 also urges knockout pad 31 and rod 32 upwardly along with the can and lid. Bevelled portions 39 of legs 23 contact bevelled portions 36 of guides 35. The interaction of the bevelled portions exerts a camming action on legs 23, moving them closer together so that legs 23 will fit between guides 35. As upward travel is continued, bevelled portions 39 oflegs 23 contact bevelled portions 38 of guide'37. Again a camming action is exerted on legs 23, moving them still closer together so that legs 23 will pass between guides 37. After legs 23 have passed into the space between guides 37, the legs 23 have been fully closed together, closing side supports 21 tightly about the body walls of can C. At the uppermost position of travel of shaft 11, can C and the lid are driven into the seaming chuck where the lid is seamed to the can by action of seaming rollers 34. This position is clearly illustrated in FIG. 9.

At the completion of the seaming operation, the cycle described in detail above is essentially reversed. Shaft 11 moves downwardly, lowering the can from the seaming chuck, out of guides 35 and 37, to the lowermost position as shown in FIGS. 5 and 6. As shaft 11 reaches its lowermost position, foot 41 contacts the base of chamber 10, forcing sub-base l4 slightly upward and raising the shoulder S of the can C above the top edge of side supports 21.

The opening of the door 42 activates switch 43 which operates cylinders 29, pivoting arms 24 about pins 27 thereby rotating sidesupports 21 to the open position. The operator may then remove the seamed can from chamber 10.

Thus it can be seen that the apparatus of the present invention allows the seaming of plastic cans at a very rapid rate, and eliminates most of the manual operations which have been necessary heretofore in the seaming of plastic cans. The present apparatus is wholly contained within the vacuum chamber and there is no requirement to modify the exterior construction of the chamber.

While the present apparatus has been described with reference to the plastic ham can, it will be understood that the invention is not limited thereby and encompasses containers in general which are seamed in the general manner described herein. Moreover, while the apparatus has been described in considerable detail for purposes of illustration, it will be understood that many modifications can be made by those skilled in the art without departing from the scope of the invention, which is defined in the appended claims.

We claim:

1. In an apparatus for vacuum sealing containers, the apparatus having a vacuum chamber into which a container and a lid for the container are placed, seaming mechanism for seaming the lid to the can, and a vertically moveable portion to carry a container upwardly from its initial position in the chamber to a raised position where the container and the lid communicate with the seaming mechanism, the improvement comprising a moveable base means communicating with said vertically moveable portion adapted to receive a container thereon, moveable container support means operably mounted within said chamber above said base means, means for partially closing said container support means about the body of a container, and guide means fixed above said container support means to engage said container support means during upward travel to fully close said container support means about a container, whereby the container is supported against distortion as the lid is seamed to the container.

2. The apparatus according to claim 1 wherein said guide means includes first and second guide portions to sequentially engage said container support means whereby said container support means is fully closed after engagement with said second guide portion.

3. In apparatus for sealing containers under vacuum having a vacuum chamber into which a container and a lid for the container are placed, the improvement comprising a plate supporting a container within said chamber, means within said chamber for engaging the sides of said container, means for raising said engaging means to bring said container into engagement with said lid while permitting said plate to drop with respect to said container thereby allowing the bottom of said container to bulge downwardly under pressure of the contents ofthe container toward said plate.

4. Apparatus as set forth in claim 3 including means for supporting said plate in fixed position with respect to said chamber during the initial operation of said raising means, said raising means being operable to raise said plate in spaced relation to said container during its operation beyond said initial operation.

5. Apparatus as set forth in claim 3 wherein said engaging means includes a pair of hinged side supports.

6. Apparatus as set forth in claim 5 including a pair ofpneumatic cylinders and pistons, and means for moving said side supports into engagement with said container when said cylinders and pistons are actuated.

7. Apparatus as set forth in claim 5 including switch means operable when a vacuum is drawn in said chamber for actuating said engaging means.

8. Apparatus as set forth in claim 3 wherein said engaging means is in frictional engagement with the sides of said container and including means for pressing said container downwardly with respect to said engaging means after said plate has dropped to lowered position to thereby bring the bottom of said container into contact with said plate.

9. In apparatus for sealing containers under vacuum having a vacuum chamber into which a container and a lid for the container are placed the improvement comprising means within said chamber for engaging the sides of said container, means for raising said engaging means to bring said container in contact with said lid, said container having a shoulder at a point above said engaging means, the engagement between said means and said container being frictional so as to permit downward movement of the container with respect to said means under pressure, means for pressing said container downwardly with respect to said engaging means until said shoulder is in engagement with said engaging means, and means for seaming said lid to said container while said shoulder is so engaged.

10. Apparatus as set forth in claim 9 including means for tightening the engagement between said engaging means as said pressing means operates to bring said shoulder into engagement with said engaging means. a

11. Apparatus as set forth in claim 8 including means for tightening said engaging means about said container as said pressing means operates to bring the bottom of said container into contact with said plate. 

1. In an apparatus for vacuum sealing containers, the apparatus having a vacuum chamber into which a container and a lid for the container are placed, seaming mechanism for seaming the lid to the can, and a vertically moveable portion to carry a container upwardly from its initial position in the chamber to a raised position where the container and the lid communicate with the seaming mechanism, the improvement comprising a moveable base means communicating with said vertically moveable portion adapted to receive a container thereon, moveable container support means operably mounted within said chamber above said base means, means for partially closing said container support means about the body of a container, and guide means fixed above said container support means to engage said container support means during upward travel to fully close said container support means about a container, whereby the container is supported against distortion as the lid is seamed to the container.
 2. The apparatus according to claim 1 wherein said guide means includes first and second guide portions to sequentially engage said container support means whereby said container support means is fully closed after engagement with said second guide portion.
 3. In apparatus for sealing containers under vacuum having a vacuum chamber into which a container and a lid for the container are placed, the improvement comprising a plate supporting a container within said chamber, means within said chamber for engaging the sides of said container, means for raising said engaging means to bring said container into engagement with said lid while permitting said plate to drop with respect to said container thereby allowing the bottom of said container to bulge downwardly under pressure of the contents of the container toward said plate.
 4. Apparatus as set forth in claim 3 including means for supporting said plate in fixed position with respect to said chamber during the initial operation of said raising means, said raising means being operable to raise said plate in spaced relation to said container during its operation beyond said initial operation.
 5. Apparatus as set forth in claim 3 wherein said engaging means includes a pair of hinged side supports.
 6. Apparatus as set forth in claim 5 including a pair of pneumatic cylinders and pistons, and means for moving said side supports into engagement with said container when said cylinders and pistons are actuated.
 7. Apparatus as set forth in claim 5 including switch means operable when a vacuum is drawn in said chamber for actuating said engaging means.
 8. Apparatus as set forth in claim 3 wherein said engaging means is in frictional engagement with the sides of said container and including means for pressing said container downwardly with respect to said engaging means after said plate has dropped to lowered position to thereby bring the bottom of said container into contact with said plate.
 9. In apparAtus for sealing containers under vacuum having a vacuum chamber into which a container and a lid for the container are placed the improvement comprising means within said chamber for engaging the sides of said container, means for raising said engaging means to bring said container in contact with said lid, said container having a shoulder at a point above said engaging means, the engagement between said means and said container being frictional so as to permit downward movement of the container with respect to said means under pressure, means for pressing said container downwardly with respect to said engaging means until said shoulder is in engagement with said engaging means, and means for seaming said lid to said container while said shoulder is so engaged.
 10. Apparatus as set forth in claim 9 including means for tightening the engagement between said engaging means as said pressing means operates to bring said shoulder into engagement with said engaging means.
 11. Apparatus as set forth in claim 8 including means for tightening said engaging means about said container as said pressing means operates to bring the bottom of said container into contact with said plate. 